heap: allow allocation in gc prologue/epilogue

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 137 matching lines @@
       crankshaft_codegen_bytes_generated_(0),
       gcs_since_last_deopt_(0),
 #ifdef VERIFY_HEAP
       no_weak_object_verification_scope_depth_(0),
 #endif
       allocation_sites_scratchpad_length_(0),
       promotion_queue_(this),
       configured_(false),
       external_string_table_(this),
       chunks_queued_for_free_(NULL),
-      relocation_mutex_(NULL) {
+      relocation_mutex_(NULL),
+      gc_callbacks_depth_(0) {
   // Allow build-time customization of the max semispace size. Building
   // V8 with snapshots and a non-default max semispace size is much
   // easier if you can define it as part of the build environment.
 #if defined(V8_MAX_SEMISPACE_SIZE)
   max_semispace_size_ = reserved_semispace_size_ = V8_MAX_SEMISPACE_SIZE;
 #endif
 
   // Ensure old_generation_size_ is a multiple of kPageSize.
   ASSERT(MB >= Page::kPageSize);
 
@@ skipping 908 matching lines @@
 
 #ifdef VERIFY_HEAP
   if (FLAG_verify_heap) {
     VerifyStringTable(this);
   }
 #endif
 
   GCType gc_type =
       collector == MARK_COMPACTOR ? kGCTypeMarkSweepCompact : kGCTypeScavenge;
 
-  {
-    GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
-    VMState<EXTERNAL> state(isolate_);
-    HandleScope handle_scope(isolate_);
-    CallGCPrologueCallbacks(gc_type, kNoGCCallbackFlags);
+  { GCCallbacksScope scope(this);
+    if (scope.CheckReenter()) {
+      AllowHeapAllocation allow_allocation;
+      GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
+      VMState<EXTERNAL> state(isolate_);
+      HandleScope handle_scope(isolate_);
+      CallGCPrologueCallbacks(gc_type, kNoGCCallbackFlags);
+    }
   }
 
   EnsureFromSpaceIsCommitted();
 
   int start_new_space_size = Heap::new_space()->SizeAsInt();
 
   if (IsHighSurvivalRate()) {
     // We speed up the incremental marker if it is running so that it
     // does not fall behind the rate of promotion, which would cause a
     // constantly growing old space.
@@ skipping 84 matching lines @@
 
   // Update relocatables.
   Relocatable::PostGarbageCollectionProcessing(isolate_);
 
   if (collector == MARK_COMPACTOR) {
     // Register the amount of external allocated memory.
     amount_of_external_allocated_memory_at_last_global_gc_ =
         amount_of_external_allocated_memory_;
   }
 
-  {
-    GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
-    VMState<EXTERNAL> state(isolate_);
-    HandleScope handle_scope(isolate_);
-    CallGCEpilogueCallbacks(gc_type, gc_callback_flags);
+  { GCCallbacksScope scope(this);
+    if (scope.CheckReenter()) {
+      AllowHeapAllocation allow_allocation;
+      GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
+      VMState<EXTERNAL> state(isolate_);
+      HandleScope handle_scope(isolate_);
+      CallGCEpilogueCallbacks(gc_type, gc_callback_flags);
+    }
   }
 
 #ifdef VERIFY_HEAP
   if (FLAG_verify_heap) {
     VerifyStringTable(this);
   }
 #endif
 
   return next_gc_likely_to_collect_more;
 }
@@ skipping 6532 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   OS::MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   OS::MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal